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This experiment was conducted to investigate the effects of inulin supplementation in low‐ or high‐fat diets on both the reproductive performance of sow and the antioxidant defence capacity in sows and offspring. Sixty Landrace × Yorkshire sows were randomly allocated to four treatments with low‐fat diet (L), low‐fat diet containing 1.5% inulin (LI), high‐fat diet (H) and high‐fat diet containing 1.5% inulin (HI). Inulin‐rich diets lowered the within‐litter birth weight coefficient of variation (CV, p = 0.05) of piglets, increased the proportion of piglets weighing 1.0–1.5 kg at farrowing (p < 0.01), reduced the loss of body weight (BW) and backfat thickness (BF) during lactation (p < 0.05) and decreased the duration of farrowing as well as improved sow constipation (p < 0.05). Sows fed fat‐rich diets gained more BW during gestation (p < 0.01), farrowed a greater number of total (+1.65 pigs, p < 0.05) and alive (+1.52 pigs p < 0.05) piglets and had a heavier (+2.06 kg, p < 0.05) litter weight at birth as well as a decreased weaning‐to‐oestrous interval (WEI, p < 0.01) compared with sows fed low‐fat diets. However, it is worth noting that the H diet significantly decreased the serum activities of superoxide dismutase (T‐SOD) and glutathione peroxidase (GSH‐Px) and increased the serum malondialdehyde (MDA) levels in sows and piglets (p < 0.05). In contrast, HI diet enhanced the activities of T‐SOD and GSH‐Px and decreased the serum MDA concentrations (p < 0.05) in sows and piglets. In summary, the fat‐rich diets fed to sows during gestation had beneficial effects on reproductive performance, but aggravated the oxidative stress in sow and piglets. Inulin‐rich diets fed to sow during gestation had beneficial effects on within‐litter uniformity of piglet birthweight and enhanced the antioxidant defence capacity of sows and piglets.  相似文献   
44.
The objective of this study was to determine the activity of steroid‐ and eicosanoid‐metabolizing enzymes in horses with varying BCSs. The BCSs of twenty non‐pregnant, anoestrous mares were determined prior to euthanasia, and tissue samples were collected from the liver, kidney, adrenal gland, ovary and endometrium. Cytochrome P450 1A (CYP1A), 2C (CYP2C), 3A (CYP3A) and uridine 5′‐diphospho‐glucuronosyltransferase (UGT) activities were determined using luminogenic substrates. The MIXED procedure of SAS was used to test the effect of BCS on enzyme activity and differences between tissues. Activity of CYP1A in adrenals was increased ( .05) in BCS 5 versus BCSs 4 and 6. Activity of CYP1A in the liver was increased (= .05) in BCS 4 versus BCSs 5 and 6. Activity of CYP1A was 100‐fold greater (< .0001) in the liver than in the adrenal, ovary and kidney. Activity of CYP2C was 100‐fold greater (< .0001) in the liver than in the adrenal, ovary and endometrium. Activity of CYP3A was only detectable in the liver. Activity of UGT in the kidney was decreased (= .02) in BCS 4 versus BCSs 5 and 6. Activity of UGT was threefold greater (< .0001) in the liver than in the kidney, whereas activity of UGT was ninefold greater (< .0001) in the kidney than in the ovary and endometrium. In general, BCS did not alter the activity of steroid‐ and eicosanoid‐metabolizing enzymes in horses. However, tissue differences in these enzymes indicated abundant hepatic metabolism in horses, which is similar to other livestock species.  相似文献   
45.
Oculomotor neurons are electrotonically coupled in three teleosts. Electron microscopy revealed axosomatic synapses with close appositions of pre- and postynaptic membranes. Similar junctions are associated with electrotonic coupling in many other cases. Stimulation of the ipsilateral eighth nerve usually initiated impulses at sites distant from the cell bodies; stimulation of the ipsilateral ophthalmic nerve initiated impulses close to the cell bodies. Electrotonic coupling may synchronize impulses arising near the, cell bodies to generate synchronous muscle contractions. Impulses arising distant from the cell bodies may lead to contractions of graded strength.  相似文献   
46.
This study aimed to investigate the effects of heavy metals, such as copper, zinc, iron, cobalt, chromium, aluminium, manganese and molybdenum, on zebrafish egg hatching rate and the subsequent survival rate of the larvae. Each metal was used in the various concentrations of0.05 mg/L, 50 mg/L and 500 mg/L to detect the threshold limit of tolerance. The study's results showed significant differences in the hatching and survival rate of larvae between the control group and most of the experimental groups when adding heavy metals in various concentrations. The highest concentration (500 mg/L) of the induced heavy metals tested in this study resulted in total egg or larval mortality within 96 hr and significantly lower egg or larval life expectancy. Among the tested metals, zinc and molybdenum had the most significant impact on hatching time, in contrast to iron that did not differentiate the results from the control group. Copper, cobalt, chromium, aluminium and manganese did affect zebrafish eggs depending on their exposure concentrations, which differentiated the results from the control group. Also, the study's findings demonstrate a significant dependence of the hatched egg heart rate on the metal concentration, and in particular, higher concentrations of metals correspond to higher heart rate. Zinc, Molybdenum and copper was proved to be the most toxic heavy metals causing increased hazard rate to mortality up to 96 hr and shorter life expectancy. Finally, skeletal deformities that occasionally observed did not significantly affect the total life expectancy of the hatched eggs.  相似文献   
47.
Viral encephalopathy and retinopathy (VER) is a serious neuropathological fish disease affecting in the Mediterranean aquaculture mainly European sea bass, Dicentrarchus labrax. It is well known that betanodaviruses are neurotropic viruses that replicate in nerve tissues, preferentially brain and retina. However, routes of entry and progression of the virus in the central nervous system (CNS) remain unclear. The role of four tissues—eye, oesophagus, gills and skin—as possible gateways of a betanodavirus, the redspotted grouper nervous necrosis virus (RGNNV), was investigated after experimental challenges performed on European seabass juveniles. The dispersal pattern of Betanodavirus at primarily stages of the disease was also assessed, using a real-time qPCR assay. The development of typical clinical signs of VER, the presence of characteristic histopathological lesions in the brain and retina and the detection of viral RNA in the tissues of all experimental groups ascertained that successful invasion of RGNNV under all experimental routes was achieved. Transneuronal spread along pathways known to be connected to the initial site of entry seems to be the predominant scenario of viral progression in the CNS. Furthermore, viraemia appeared only after the installation of the infection in the brain.  相似文献   
48.
A. C. Pappas 《EPPO Bulletin》2000,30(2):269-274
Out-of-season tomatoes grown in unheated glasshouses in Greece annually suffer considerable losses from grey mould induced by Botrytis cinerea. Characteristic soft rots of young fruit by the calyx end, flower abortions and stem lesions or cankers are the most commonly occurring symptoms of the disease. Severe ghost spots on fruit only appear when fungicides inhibiting spore germination are not applied. Conidia produced on plant debris of the previous year's crop serve as primary inoculum. Disease starts in late autumn, increases rapidly during the winter period and ceases abruptly at the end of April. Infections caused by isolates resistant to dicarboximides or to both dicarboximides and benzimidazoles are uncommon at the beginning of each new crop cycle. These increase substantially as the season progresses and decline after cessation of fungicide sprays. By contrast, infections caused by benzimidazole-resistant strains are stable throughout the growing season. Efficient disease control implies use of proper glasshouse covering material, adequate indoor air circulation, partial night heating, strict indoor and outdoor hygiene and regular fungicide sprays. When disease pressure is low, application only of conventional compounds like dichlofluanid and chlorothalonil is recommended. Under conditions favourable to Botrytis infections, mixtures of conventional compounds with reduced strength specific botryticides should preferably be applied. Such regimes efficiently minimize losses from fungicide resistance development and ghost spot.  相似文献   
49.
Iprodione, in ethanolic solution, was found to undergo structural rearrangement over a period of days to give a solid product which was shown by mass spectrometry to be an isomer. Mechanistic considerations led to a proposed structure, which was verified by synthesis of an authentic specimen by an unambiguous route. The biological implications of these findings are discussed.  相似文献   
50.
Benomyl, prochloraz or procymidone, applied as an overall plant spray at the openflower stage, effectively suppressed Botrytis cinerea fruit rot, whereas no control was achieved by foliar application only. Fruit rot was prevented using procymidone applied to the soil 12 days before inoculation of the flowers, whereas benomyl or prochloraz gave little or no control, respectively when applied in the same manner. Bioassays, using Penicillium expansum on leaf and flower extracts of strawberry plants growing in soil treated with procymidone, showed the presence of an inhibitory compound with the same RF value on thin-layer chromatography as that of procymidone. Analysis by gas chromatography and identification by gas chromatography—mass spectrometry established that the fungicide procymidone was translocated from the root system of strawberry plants to the leaves and flowers.  相似文献   
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